1. Field of the Invention
The invention relates to an autonomous container ship with a hull containing a propulsion system. This ship is able to transport containers from large ports equipped with a loading system and unload them at small ports lacking such equipment.
2. Description of the Related Art
The transport of goods is indeed one of the mainsprings of our market economy. The globalization of international trade, the development of xe2x80x9cjust in timexe2x80x9d policies, and the increasing demand for responsiveness are continuously fostering the growth of land transport with development of costly highway infrastructures harmful to the environment.
Numerous container ships with a large container-carrying capacity and deep draft exists such as those described in Jane""s Intermodal Transportation, pages 315, 338, and 341. One example of these large-capacity container ships is the ALIANCA BRASIL with a capacity of 2200 containers, a speed of 20.4 knots, a length of 200.23 m, and a draft of 12.0 m. One of the smallest of these container ships is the HERA with a capacity of 198 containers, a speed of 12.5 knots, a length of 88 m, and a draft of 4.6 m.
These container ships generally unload in ports equipped with heavy handling equipment. Ports able to receive existing container ships are few in number and cannot deliver goods close to their utilization sites.
The keels may of different types.
They may of the single-hulled type.
They may also be of the multi-hulled catamaran or trimaran type depending on whether they have two or three hulls.
Depending on specific needs, the keel may be of the mixed type known as monocatamaran, namely single-hulled at the bow and catamaran at the stern.
U.S. Pat. No. 5,038,696 describes a monocatamaran whose hull has been specially designed for hydrodynamic flow considerations under the water line to increase the speed and stability of the ship. These are the goals of the present invention, but focusing on a particular application of the type of container ship considered, namely with a large payload in relation to its displacement and stability of the ship during handling operations.
In order to increase the speed of the ship and decrease fuel costs, tunnel hulls accommodating thrusters, particularly screw propellers, have been proposed.
U.S. Pat. No. 4,371,350 discloses a ship with a thruster tunnel having a transverse configuration favorable to hydrodynamic flow along the stream lines. These concerns of improving hydrodynamic flow are found in the present invention but they are incorporated into a special architectural principle responding to the above-defined objectives.
In particular, the invention relates to a range of small and medium-sized ships that can carry merchandise from one small port to another in containers.
This range is composed of ships able to transport a maximum number of containers equal to two, four, ten, twenty, thirty, fifty, and a hundred.
A principal feature of the ship is its full autonomy, enabling it to load and/or unload containers in a port not equipped with a handling system and having a water depth of less than 4 meters.
The range of ships according to the invention arose from this view with the concern of developing complementarity between highway transport and sea/river transport.
The goal is to provide sea links to serve a multitude of inland ports that have been exploited little or not at all for goods transport. Another goal is for highway container carriers to load goods from these ports for local distribution to optimize land delivery distances.
One of the objectives of the present invention is to provide trucking companies with a mobile xe2x80x9csea/river superhighwayxe2x80x9d infrastructure matching the land superhighway system.
A second objective is to increase the responsiveness of sea-land transportation by shipping small quantities at frequent intervals.
A third objective is to provide river/sea service with substantial independence of maneuver, an optimized dock-to-dock path, and unloading/loading systems matching these constraints. This objective implies being able to carry a payload which is large relative to the displacement of the ship.
A fourth objective is to provide transportation under service and mileage conditions comparable to those of highways.
The purpose of the tunnels in the stem of the hull is, according to the invention:
to build a flush-fitting propulsion system into the hull,
to protect the propulsion elements from jolts when sailing in shallow waters,
to improve the efficiency of the propulsion system by flow of stream lines toward the stem of the ship,
to clear the stem of the ship so that it can come closer to the banks.
To meet the above-defined objectives, the invention relates to an autonomous container ship of the type having a keel, a propulsion system, a container loading and unloading system, and a balancing system, characterized in that the keel is of the type wherein the hull contains the propulsion system and in that the ship has a carrying system for carrying containers from large ports equipped with a container loading and unloading system to small ports lacking such equipment and having a water depth less than 4 meters. The ship includes a propulsion system that allows the ship to sail at cruising speed at sea and at estuary and port speeds, a loading and unloading system adapted to these ports lacking equipment, and a balancing system for balancing the ship at sea serving to stabilize and trim the ship during handling.
This container ship is moreover characterized in that the propulsion system also ensures maneuverability in ports.
In addition, the ship according to the invention enables a large payload relative to its displacement to be carried. This goal is achieved by equipment providing a common power supply for propulsion and handling, and a handling system usable both on board and on land.